IBM 689912U Hardware Maintenance Manual - Page 91

Undetermined Problem Check the power supply voltages. See "Power Supply" on page 28. If the voltages are correct, return here and continue with the following steps. 1. Power-off the computer. 2. Remove or disconnect the following, one at a time: a. Non-IBM devices b. External devices (modem, printer, or mouse) c. Any adapters d. Riser card e. Memory modules Before removing or replacing memory modules, see "System Board Memory" on page 248. f. Extended video memory g. External Cache h. External Cache RAM i. Hard disk drive j. Diskette drive 3. Power-on the computer to re-test the system. 4. Repeat steps 1 through 3 until you find the failing device or adapter. If all devices and adapters have been removed, and the problem continues, replace the system board. See "Replacing a System Board" on page 83. Replacing a Processor For Pentium® processors, install the processor with the beveled corner aligned with the beveled corner of the processor socket. For Type 6588, 6888, and other Types that have Pentium II processors, see "Microprocessor Removal (Type 6588, 6888)" on page 284. For Dual Pentium II processors, jumper the processor speed to the slowest speed processor. When a second Pentium Pro or Pentium II microprocessor is installed for Dual processor operation, the processor revision must be one under, the same, or one above from each other. To find the processor revision level, go to the configuration Setup (see "Setup Utility Program" on page 220) and select: 1. Advanced Setup 2. Processor Control 3. Processor ID The processor ID has four numbers, such as 0650. The first two numbers, 06, designates the Pentium processor. The second two numbers, 50, designates the processor revision level. Service Information 81